I'm sorry, but using a "sub 4 sub" site is beyond pointless. Unless these subscribers are actually viewing your content and engaging (which is highly doubtful) then please, for the love of god, STOP DOING THIS.
Use AddMeFast for social engagement like views and likes if you're trying to rank a video fast.
So the solution to your problem is STOP before you get yourself banned. YouTube can tell all of those accounts are spam so they get deleted. That's why your subs keep dropping. This is nothing new.